Fun and Games, directed by Gerd Oswald.
On the run after witnessing a gambling murder, a boxer is picked up by an alien puppet-master and given a proposition: he and an Earth woman will be sent to the Arena planet in a fight to the death against another alien couple, all for the amusement of unseen spectators.
Whichever side loses: their planet is also destroyed.
That may seem excessive but the boxer understands: people watch violence "for kicks". Gambling murders both on Earth and beyond.
The actual combat is a relatively minimal part of the story; we don't even get to the planet until the second half of the program. The alien opposition have rudimentary rubber masks and costuming.
Minor SF action with a lot of conversation, not really Outer Limits material.
Nick Adams is the star, an actor who always confused me. Not really leading man material, but he had his own TV shows. One of Hemingway's continuing characters was "Nick Adams" and I was unclear if there was supposed to be a connection.
The story prefigures Star Trek Arena, where Kirk fights the reptilian Gorn. With maybe a little The Gamesters of Triskelion thrown in.
It's not clear if the writers of either series read it, but Fredric Brown's 1944 short story Arena has a similar concept.
Photographed by Kenneth Peach.
The Blu-ray commentary track is by David J Schow. He is adamant this is not derived from Fredric Brown's short story. How he is so certain I do not know.